1. Field of the Invention
The invention relates to a fender assembly for a heavy-duty vehicle. In one of its aspects, the invention relates to fender assembly comprising a fender mounted to a support arm by a vibration decoupler that dampens the vibrations acting on the fender. In another of its aspects, the invention relates to a mounting bracket assembly for mounting a vehicle fender to a frame.
2. Related Art
Heavy-duty vehicles, such as a semi-tractor, use fender assemblies to cover the otherwise exposed drive wheels of the tractor. Many fender assemblies are adjustable to accommodate the various semi-tractor configurations and fender types. A common approach for accomplishing the adjustability of the fender assembly is to provide the assembly with an adjustable mounting bracket, which mounts the fender to the vehicle frame in a manner to permit the movement of the fender relative to the vehicle frame and wheels.
Prior mounting brackets comprise an elongated arm that is connected to and laterally offset from a rotationally adjustable mount. The elongated arm mounts a portion of the fender and the rotationally adjustable mount is secured to the vehicle frame. The relative position of the fender to the vehicle and wheels can be adjusted by rotating the rotationally adjustable mount to change the orientation of the elongated arm. The arm and mount can be made from a single piece or from multiple pieces. The rotatable mount can comprise a tube that receives a bolt secured to the frame by a nut. The mount can be rotated by loosening the nut and rotating the tube and re-tightening the nut.
One problem with the prior adjustable brackets is that the fender is typically connected directly to the elongated arm by a traditional mechanical fastener, such as a bolt, with or without an intervening metal clamp. The mechanical connection between the fender and the arm provides for a direct transfer of the forces acting on the fender or bracket to the other of the fender or bracket without any dampening or uncoupling of the forces. The undamped or uncoupled forces can over time fatigue either of the fender or the mounting bracket, resulting in their failure.
The problem is more acute with the fender, which is typically made from a relatively thin material, often plastic, and the fastener passes directly through an opening in the fender and clamps the fender to the arm. The aerodynamic forces acting on the fender and the road forces acting on the fender through the arm result in repeated loads acting on the fender at the inner surface of the fender opening. The forces acting on the inner surface of the opening tend to induce the propagation of cracks or other failure modes in the fender at the opening.
In GB 310,781, a fender is mounted to the vehicle steering system through an arm that permits the rotation of the fender corresponding to the turning of the wheel. Fender brackets are connected to the fender through bushed joints. U.S. Pat. No. 5,511,808 also discloses a fender mounted to the vehicle steering system through an arm that permits the rotation of the fender corresponding to the turning of the wheel. The fender mounting bracket includes a torsion bushing through which the fender can articulate with respect to the frame during turning of the wheel. The fender is spaced from the torsion bushing resulting in moment induced forces, attributable to the loading of the fender, to act on the connection of the fender and the arm and increase the magnitude of the forces acting thereon.
According to the invention, a fender assembly for a vehicle comprises a longitudinal frame carrying ground-engaging wheels supporting the frame above a road surface and positioned laterally of the frame. The fender assembly comprises: a fender adapted to overlie at least one of the wheels and having an upper surface and a lower surface of a relatively linear cross dimension; a support arm having a first portion adapted to mount to the vehicle frame and an elongated, relatively linear second portion extending laterally from the first portion and across an upper or lower surface of the fender in alignment with the linear cross dimension; and at least one vibration-decoupling connector mounted between the support arm and to the fender. The vibration-decoupling connector includes a vibration dampening isolator adapted to dampen vibrations between the support arm and the fender when the support arm is mounted to the frame.
The fender can have an arcuate longitudinal profile, and a surface of the isolator is in contact with the fender upper or lower surface of the fender, and the isolator surface has a longitudinal profile complementary to the arcuate longitudinal profile of the fender.
The isolator preferably comprises an elastomeric body with a relatively wide surface that is in contact with, and conforms to, the upper or lower surface of the fender and can have a relatively wide surface that is in contact with, and conforms to, the upper or lower surface of the fender. It is preferred that the isolator has an elastomeric body and the elastomeric body forms the relatively wide surface.
The vibration-decoupling connector can further comprises a first fastener assembly that connects the isolator to the fender and a second fastener assembly that connects the isolator to the support arm. The first fastener assembly preferably comprises a mechanical fastener that compresses the isolator""s relatively wide surface against the fender. The mechanical fastener can be an internally threaded bushing in the isolator and a threaded fastener passing through the fender and threaded into the internally threaded bushing. The second fastener assembly can comprise an internally threaded bushing in the isolator, a strap overlying the support arm and the isolator, and a threaded fastener passing through the strap and threaded into the internally threaded bushing to retain the support arm between the strap and the isolator.
The isolator is preferably formed with a channel that complements a profile of the support arm and at least a portion of the support arm is received within the isolator channel. The isolator can further include a spacer for adjusting the spatial relationship between the support arm and fender, with the spacer preferably being in direct contact with the fender.
In one embodiment, the first fastener assembly comprises a plate positioned on the opposite side of the fender from the isolator and at least one mechanical fastener passing through the fender and clamping the fender between the plate and the isolator. The second fastener assembly comprises a sleeve in which the support arm is received and the sleeve is mounted to the isolator independent of the first fastener assembly. Preferably, the second fastener further comprises a wall positioned on the isolator and an embossment on the isolator that is deformed over a portion of the wall to retain the sleeve wall on the isolator. The sleeve wall can have an opening through which the isolator embossment extends and is deformed over the wall adjacent the sleeve wall opening.
The isolator embossment can have an axial opening through which the at least one mechanical fastener passes, and the clamping pressure of the at least one fastener deforms the embossment over the sleeve wall adjacent to the embossment axial opening. The embossment is deformed radially outwardly relative to the axial opening.
The first fastener further comprises a sleeve received within the axial opening to limit the compression of the embossment by the mechanical fastener. In this configuration, the mechanical fastener preferably comprises a threaded bolt having a head and a threaded stem and a nut threadably mounted to the stem. A washer can be disposed between the upper portion of the embossment and either of the head or bolt whereby the washer contacts the upper portion of the embossment.
The vibration-decoupling connector comprises a pair of plate-like members with surfaces that are in contact with and conform to the upper and lower surfaces of the fender and a sleeve having an opening that receives the support arm, and wherein one of the plate-like members and the sleeve forms the isolator. Preferably, the isolator is formed of an elastomeric material and at least one of the isolator, body, and plate is a rigid plastic material.
The vibration-decoupling connector further comprises a first fastener assembly connecting the isolator to the fender and a second fastener assembly connecting the isolator to the support arm. The first fastener assembly comprises a mechanical fastener that compresses the isolator relatively wide surface against the fender. The first fastener assembly can also comprise a plate positioned on the opposite side of the fender from the isolator and at least one mechanical fastener passing through the fender and clamping the fender between the plate and the isolator.
In another embodiment of the invention, a bracket assembly for mounting a vehicle fender to a vehicle frame overlying a ground engaging wheel positioned laterally of the frame comprises: a support arm having a first portion adapted to mount to the vehicle frame and an elongated linear second portion extending laterally from the first portion and adapted to extend laterally across an upper or lower surface of the fender; and a pair of vibration-decoupling connectors mounted to the support arm and adapted to mount to the fender. Each of the vibration-decoupling connectors include a vibration dampening isolator adapted to dampen vibrations between the support arm and the fender to reduce the transfer of vibration forces between the frame and the fender when the support arm is mounted to the frame.
The isolator preferably has a relatively flat surface that is in direct contact with the upper or lower surface of the fender. The isolator can include an elastomeric body that isolates vibrations between the support arm and the fender. Preferably, the elastomeric body has a relatively flat surface that is in direct contact with the upper or lower surface of the fender.
A first fastener assembly can be used to connect the isolator to the fender and a second fastener assembly can be used to connect the isolator to the support arm. The first fastener assembly comprises a mechanical fastener that compresses the isolator relatively wide surface against the fender. The first fastener assembly can also include a plate positioned on the opposite side of the fender from the isolator and at least-one mechanical fastener passing through the fender and clamping the fender between the plate and the isolator. The second fastener assembly can also include a sleeve in which the support arm is received and the sleeve is mounted to the isolator independent of the first fastener assembly.
In yet another embodiment, a vibration-decoupling connector comprises: an isolator having a first surface for directly contacting either the upper or lower surface of the fender; a first fastener assembly adapted to connect the isolator to the fender; and a second fastener assembly adapted to connect the isolator to the support arm. The isolator dampens vibrations between the support arm and the fender to reduce the transfer of vibration forces between the frame and the fender when the support arm is mounted to the frame.